From 792eb4e4f84515afe5c1b5c5292193fa274b83e4 Mon Sep 17 00:00:00 2001
From: beurmuz <fallinta2@gmail.com>
Date: Mon, 28 Nov 2022 23:01:17 +0900
Subject: [PATCH] #9 22.11.28 > dfs

---
 src/inf/dfs,bfs/5_rere.js     | 22 +++++++++++++++++
 src/inf/dfs,bfs/7_1_rerere.js | 46 +++++++++++++++++++++++++++++++++++
 src/inf/dfs,bfs/README.md     |  2 +-
 3 files changed, 69 insertions(+), 1 deletion(-)
 create mode 100644 src/inf/dfs,bfs/5_rere.js
 create mode 100644 src/inf/dfs,bfs/7_1_rerere.js

diff --git a/src/inf/dfs,bfs/5_rere.js b/src/inf/dfs,bfs/5_rere.js
new file mode 100644
index 00000000..35809313
--- /dev/null
+++ b/src/inf/dfs,bfs/5_rere.js
@@ -0,0 +1,22 @@
+"use strict";
+
+function solution() {
+  let answer = [];
+  let queue = [];
+  queue.push(1); // 루트 노드 먼저 넣어놓고 시작하기
+
+  while (queue.length) {
+    let v = queue.shift(); // 맨 앞 노드 하나 빼기 (빼는 순간 방문했다고 침)
+    answer.push(v);
+
+    for (let nextVertex of [v * 2, v * 2 + 1]) {
+      if (nextVertex > 7) continue; // 7보다 크면 건너뜀
+      queue.push(nextVertex); // v의 자식 노드들(v*2, v*2+1)을 queue에 넣어줌
+    }
+  }
+  return answer;
+}
+
+console.log(solution());
+
+// 주로 상태트리 문제 (ex. 출발에서 도착지점으로 갈 때의 최단 거리를 구해라)
diff --git a/src/inf/dfs,bfs/7_1_rerere.js b/src/inf/dfs,bfs/7_1_rerere.js
new file mode 100644
index 00000000..0a30a0bc
--- /dev/null
+++ b/src/inf/dfs,bfs/7_1_rerere.js
@@ -0,0 +1,46 @@
+"use strict";
+
+function solution(n, board) {
+  let answer = 0;
+  let dx = [-1, -1, 0, 1, 1, 1, 0, -1];
+  let dy = [0, 1, 1, 1, 0, -1, -1, -1];
+
+  function dfs(x, y) {
+    board[x][y] = 0;
+
+    for (let k = 0; k < 8; k++) {
+      let nx = x + dx[k];
+      let ny = y + dy[k];
+
+      if (nx >= 0 && nx < n && ny >= 0 && ny < n && board[nx][ny] === 1) {
+        console.log(nx, ny);
+        dfs(nx, ny);
+      }
+    }
+  }
+
+  for (let i = 0; i < n; i++) {
+    for (let j = 0; j < n; j++) {
+      if (board[i][j] === 1) {
+        answer++;
+        console.log(i, j);
+        dfs(i, j);
+        console.log("dfs end");
+      }
+    }
+  }
+
+  return answer;
+}
+
+let arr = [
+  [1, 1, 0, 0, 0, 1, 0],
+  [0, 1, 1, 0, 1, 1, 0],
+  [0, 1, 0, 0, 0, 0, 0],
+  [0, 0, 0, 1, 0, 1, 1],
+  [1, 1, 0, 1, 1, 0, 0],
+  [1, 0, 0, 0, 1, 0, 0],
+  [1, 0, 1, 0, 1, 0, 0],
+];
+
+console.log(solution(7, arr));
diff --git a/src/inf/dfs,bfs/README.md b/src/inf/dfs,bfs/README.md
index 4ea8c052..42096f67 100644
--- a/src/inf/dfs,bfs/README.md
+++ b/src/inf/dfs,bfs/README.md
@@ -17,7 +17,7 @@
 |  2   |    X     | 22.11.28😢 |
 |  3   |    X     |  22.11.28  |
 |  4   |    X     | 22.11.28😢 |
-|  5   |    X     |     O      |
+|  5   |    X     | 22.11.28😢 |
 |  6   |    X     |     O      |
 | 7-1  |    △     |  22.11.28  |
 | 7-2  |    △     |     O      |